1. Technical Field
The present invention relates to a projector.
2. Related Art
There has been what is called a three-panel projector using three reflective liquid crystal panels, each of which is, for example, formed of LCOS (Liquid Crystal On Silicon), provided for respective three colors, R (red), G (green), and B (blue) as light modulators that modulate incident light fluxes in accordance with image information (see JP-A-2009-036819, for example).
The projector described in JP-A-2009-036819 includes a wire grid for each of the color light fluxes, and the wire grid separates the color light flux with which the corresponding reflective liquid crystal panel is illuminated and the color light flux modulated by the liquid crystal panel from each other based on polarization. The color light fluxes modulated by the reflective liquid crystal panels and separated by the wire grids based on polarization are combined in a color combining device, and the combined light is projected on a screen through a projection lens.
When optical parts are disposed in a densely packed arrangement so that the size of a projector is reduced, the optical path of a specific light flux among the three color light fluxes cannot be separated from an optical part disposed in the optical path of another color light flux by a sufficiently large distance. To keep the distance described above sufficiently large while maintaining the size of the projector to be small, it is, for example, conceivable to extend the distance between the wire grid disposed in the optical path of the specific color light flux and the color combining device, that is, extend only the optical path length of the specific color light flux.
All the reflective liquid crystal panels, however, need to be disposed in the back focal position of the projection lens so that sharp image light fluxes are projected through the projection lens. Simply extending the optical path length of the specific color light flux between the reflective liquid crystal panel that modulates the specific color light flux and the projection lens inevitably requires the optical path lengths of the other color light fluxes to be extended, disadvantageously resulting in no reduction in size of the optical apparatus.